The present invention relates generally to the field of exercise bicycles or ergometers and, more particularly, to those devices which eliminate the need for brake pads or similar mechanical means for applying resistance to the flywheel.
The patent literature and market disclose many types of exercise bicycles, or ergometers, and means associated therewith for determining work output. However, conventional exercise bicycles such as are disclosed therein are characterized by either inaccurate or fairly complicated means for measuring work input.
A simple and commonly used design for exercise bicycles incorporates an adjustable friction brake mechanism in which the degree of tension applied by brake pads upon the flywheel is varied by rotating a control knob which is operatively connected to the brake pads by a caliper-type linkage. The degree of tensioning or load resistance cannot be accurately calibrated according to the positioning of the control knob, however, because as the brake pads become worn the control knob must be turned a relatively greater amount in order to attain the same degree of tensioning previously applied. Thus, the operator must continually guess where the control knob should be positioned to obtain the desired load resistance. This problem is not remedied by the fact that the exercise bicycle may be equipped with an indicator means for measuring work rate input, since this measurement is dependent upon both load resistance and rate of pedaling. Hence, the operator may still be unable to adjust the resistance load to the desired setting.
Also, previous work rate input indicators have themselves been characterized by relatively inaccurate or complicated and expensive constructions. Thus, those that employ electronic circuitry or electrical motor/generator means are disadvantaged by their expense, while mechanical devices, such as those employing spring tensioning means are often inaccurate or subject to breakdown and replacement of worn parts.
Another benefit not provided by any known types of exercise bicycles or ergometers concerns the ability to provide muscular exertion of the arms and upper body in addition to the lower torso and legs, and to permit measurement of the total work rate input provided by the muscular exertion of these body parts.
The following list of patent references disclose various types of exercise bicycles and ergometers:
______________________________________ Patent No. Inventor Issued ______________________________________ Group I 3,192,772 Tarter July 6, 1965 3,360,263 Tsuru December 26, 1967 3,845,663 Blomberg et al. November 5, 1974 3,995,491 Wolfla, II December 7, 1976 4,007,927 Proctor February 15, 1977 4,291,872 Brilando et al. September 29, 1981 Group II 2,784,591 Shoor March 12, 1957 3,767,195 Dimick October 23, 1973 3,802,698 Burian et al. April 9, 1974 3,845,756 Olsson November 5, 1974 3,984,666 Barron October 5, 1976 4,112,928 Putsch September 12, 1978 ______________________________________
It may be noted that those patents falling in the first category all disclose mechanical tensioning means for applying variable resistance to a rotatable flywheel. The Wolfla and Tsuru patents disclose the use of a belt or strap wrapped around the circumference of the flywheel as the braking means while the other patents in this category employ brake pads or a drag roller as the adjustable braking means.
Those patents falling in the second category are grouped together for their disclosure of fairly sophisticated electronic means for measuring energy or work output. None of devices disclosed in these patents is characterized by the simplicity of the present invention.
Moreover, none of the above patents in either Group I or II above disclose an exercise bicycle which permits muscular exertion of both the legs and the arms of the operator.